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liq [111]
3 years ago
15

A ball is thrown upward with an initial velocity of 40 feet per second from ground level. The height of the ball, in feet, after

t seconds is given by h= -16t^2 + 40t. At the same time, a balloon is rising at a constant rate of 10 feet per second. Its height, in feet, after t seconds is given by h = 10t. Find the time it takes for the ball and the balloon to reach the same height and explain.
Mathematics
1 answer:
Elena L [17]3 years ago
6 0

It takes 1.875 seconds for the ball and the balloon to reach the same height

Step-by-step explanation:

A ball is thrown upward with an initial velocity of 40 feet per second from ground level

  • The height of the ball, in feet, after t seconds is given by h= -16 t² + 40 t

At the same time, a balloon is rising at a constant rate of 10 feet per second

  • Its height, in feet, after t seconds is given by h = 10 t

We need to find the time it takes for the ball and the balloon to reach the same height

∵ The height of the ball is given by h = -16 t² + 40 t

∵ The height of the balloon is given by h = 10 t

∵ They start at the same time t

∵ They have the same height h

Equate the two equations of h to find t

∴ -16 t² + 40 t = 10 t

- Subtract 10 t from both sides

∴ -16 t² + 30 t = 0

- Take -2 t as a common factor

∴ -2 t(8 t - 15) = 0

Equate -2 t by 0 and 8t - 15 by 0

∵ -2 t = 0 ⇒ divide both sides by -2

∴ t = 0 ⇒ initial time

∵ 8 t - 15 = 0 ⇒ add 15 to both sides

∴ 8 t = 15 ⇒ divide both sides by 8

∴ t = 1.875 seconds

It takes 1.875 seconds for the ball and the balloon to reach the same height

Learn more:

You can learn more about the equations in brainly.com/question/2977815

#LearnwithBrainly

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